1. Field of the Invention
The present invention relates to an electrical connector configured so that a signal transmission medium inserted in a medium insertion path is engaged with and retained by latch lock parts.
2. Description of Related Art
Generally, in various electric devices, etc., various electrical connectors are widely used as means for electrically connecting various signal transmission media such as flexible printed circuits (FPC) and flexible flat cables (FFC). For example, in an electrical connector used when mounted on a printed wiring board like below-described Japanese Patent Application Laid-Open No. 2005-078908, a signal transmission medium consisting of, for example, a FPC or FFC is inserted from a front-end-side opening of a medium insertion path formed by inner wall surfaces of an insulating housing (insulator) to the interior thereof, and an actuator (turning operation means) is then turned so as to be pushed down toward a connection working position in a connector front side or rear side by the operating force of an operator. As a result, latch lock parts disposed so as to be opposed to engagement position determining parts provided at terminal parts of the signal transmission medium are moved so as to be dropped and achieve a latched state, and the engagement force of the latch lock parts with respect to the engagement position determining parts of the signal transmission medium in this process is configured to retain the terminal parts of the signal transmission medium in an approximately immobile state.
On the other hand, in an electrical connector provided with a so-called one-action auto-lock mechanism, latch loc parts are elastically displaced so as to be placed over a signal transmission medium inserted in an insulating housing, and the latch lock parts are configured to then drop in engagement position determining parts of the signal transmission medium to carry out engagement. When an electrical connector having such a one-action auto-lock mechanism is used, the signal transmission medium is retained in an approximately immobile state only by the insertion of inserting the signal transmission medium to a predetermined position in the electrical connector, wherein working efficiency is improved.
In this manner, general electrical connectors widely employ the configuration in which a signal transmission medium is retained by achieving a latched state by moving the latch lock parts so that the parts are engaged with the engagement position determining parts of the signal transmission medium from the state in which the latch lock parts are facing a first-side surface of the signal transmission medium inserted in the medium insertion path. However, the thickness of the signal transmission media to be inserted in the electrical connector are varied, and there is a problem that the latching amount, in other words, the engagement amount of the latch lock parts are varied depending on the variation amounts of the signal transmission media.
More specifically, even when the variation amounts in the thickness of the signal transmission media are within set dimensional tolerance, the latch amounts of the latch lock parts with respect to the engagement position determining parts are small for the signal transmission media having thin sizes; therefore, the retention force of the signal transmission media may be reduced, and the signal transmission media may fall off from the electrical connector. On the other hand, in a case in which a signal transmission medium having a thick size is inserted in the electrical connector, the latch amounts of the latch lock parts with respect to the engagement position determining parts of the signal transmission medium are large, and sufficient retention force of the signal transmission medium is obtained; however, when the latch lock parts are to be detached from the signal transmission medium by carrying out an unlock operation, the movement distances (stroke distances) required for detachment of the latch lock parts have to be largely ensured to correspond to the thickness of the signal transmission medium, and the size of the entirety of the electrical connector tends to be increased by the increased amount of the thickness.
Moreover, in order to enable the signal transmission medium to be smoothly inserted to the electrical connector, problems, for example, that the engagement position determining parts provided in the signal transmission medium are caught by intermediate parts of the medium insertion path have to be eliminated; and, in order to do that, guide wall parts which guide both-side edges of the signal transmission medium have been conventionally provided in the insulating housing. Since edge parts of the signal transmission medium contact or collide with the guide wall parts of the insulating housing, the thicknesses of the guide wall parts are increased to impart them predetermined strength so that deformation or damage are not caused in the guide wall parts by the collision force thereof. Therefore, the conventional electrical connectors have an inclination that the sizes of the electrical connectors are increased by the amounts of the necessity to increase the thickness of the guide wall parts.
We disclose the prior art that we are aware of to be materials for the examination of the application as follows.
[Unexamined Publication Gazette 1]
    JP 2005-078908 A (Patent Application Laid-Open)